title: Exercised-induced increase in lipid peroxidation parameters in amenorrheic female athletes.
abstract: OBJECTIVE
  To determine plasma lipid peroxidation parameters in eumenorrheic and amenorrheic athletes and to evaluate differences in their response to exercise-induced oxidative stress. In female athletes, intense physical exercise has been shown to be associated with an increased occurrence of menstrual dysfunction with lower levels of E2. Recently, a protective role has been demonstrated for estrogens as free radical scavengers.
  
  
  METHODS
  Comparison of eumenorrheic and amenorrheic athletes before and after an acute bout of exercise.
  
  
  METHODS
  Academic Research Environment.
  
  
  METHODS
  Seven eumenorrheic (normally menstruating) and seven amenorrheic (<3 menses/year) female athletes aged 18 to 35 years participating in regular training.
  
  
  METHODS
  Plasma and low-density lipoprotein oxidation parameters, plasma E2 and vitamin E levels, and creatine kinase activity.
  
  
  RESULTS
  Both the amenorrheic and eumenorrheic athletes demonstrated a significant decrease in the lag time of conjugated diene formation after exercise (P < 0.01), with greater magnitude of change occurring in the amenorrheic athletes (P < 0.05). In addition, postexercise samples from amenorrheic (but not eumenorrhic) athletes showed a significant (P < 0.01) increase in oxysterol formation as compared to baseline values. Amenorrheic athletes also demonstrated a significantly higher baseline creatine kinase activity and a nonsignificant (P = 0.04) trend of an increase in creatine kinase activity after exercise.
  
  
  CONCLUSIONS
  The results of this study shows that amenorrheic female athletes demonstrate an increased potential for lipid peroxidation after exercise. This could be related to lower plasma E2 levels in this group, considering the strong free radical scavenging ability of estrogens identified recently.
authors.affiliation: Department of Internal Medicine, University of Cincinnati Medical Center, Ohio 45267-0540, USA.
authors.forename: S
authors.initials: S
authors.lastname: Ayres
authors.forename: J
authors.initials: J
authors.lastname: Baer
authors.forename: M T
authors.initials: MT
authors.lastname: Subbiah
mesh_terms: D000293:Adolescent; D000328:Adult; D000568:Amenorrhea / Q000097:blood / Q000378:metabolism*; D003402:Creatine Kinase / Q000097:blood; D004958:Estradiol / Q000097:blood; D015444:Exercise; D005260:Female; D006801:Humans; D008054:Lipid Peroxides / Q000378:metabolism*; D012016:Reference Values; D013177:Sports
chemical_list: D008054:Lipid Peroxides; D004958:Estradiol; D003402:Creatine Kinase